Nowadays any larger commercial aircraft usually comprises a water system that on board the aircraft in flight provides water of drinking quality. A standard water system of an aircraft supplies water consumers, for example toilets, galleys, water dispensers and the like, from a central water supply system, and removes used water, depending on the type of soiling, to a gray water system or to a black water system.
Fresh water is usually filled into the water system of the aircraft, by way of water supply systems, when the aircraft is on the ground, for example with the use of tanker trucks. Because of the danger of propagation of microbiological impurities in a water system it is necessary to keep the bacterial count within specified limits. In water systems, at present, disinfection is used in order to achieve a reduction in the microbiological bacterial count. For disinfection, a chemical disinfectant is added to the water system, and by means of multiple rinses the disinfectant is channeled through the water system so that disinfection takes place. Furthermore, treatment of the fresh water by means of UV light during the filling up of the aircraft, i.e. by means of physical disinfection, is known.
In principle it is known not to limit the water supply in aircraft water systems to the use of a previously filled-in quantity of potable water; instead there are also concepts for implementing the water supply in part also by means of water generators, for example in the form of a fuel cell, and to couple it to a water supply from water tanks. Disinfection of such an expanded water system would be very expensive, because when compared to conventional aircraft water systems a larger number of different water-conducting devices would have to be subjected to disinfectants, and consequently during times periods when the aircraft is on the ground additional work has to be carried out, which due to the considerable expenditure of time and personnel is cost intensive. In addition, in an alternative use of water from water generators, disinfection with chemical disinfectants is not applicable if flight-specific and safety-relevant systems, e.g. engines, are subjected to the water.
DE 10 2006 002 470 and WO 2007 028 622 A1 show a fuel cell system for supplying potable water and oxygen to an aircraft.
Accordingly, it can be desirable to provide an improved water system and method for reducing germs in a water system. In addition, other objects, desirable features and characteristics will become apparent from the subsequent summary and detailed description, and the appended claims, taken in conjunction with the accompanying drawings and this background.